1. Field of the Invention
The present invention relates in general to fluid flow detectors and in particular to a reliable, low cost, disposable sensor for automated plastic extrusion systems in which an alarm is given if a rupture disk fails and liquified plastic flows through the pressure relief piping.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
There are many different types of rupture disk assemblies or safety pressure relief devices that are used as protective devices on tanks, receptacles, or conduits in which excessive fluid pressure may develop. They are designed to burst under a predetermined pressure. A few of the representative types of such assemblies are disclosed in U.S. Pat. Nos. 2,922,544, 2,194,159, 3,091,359, 3,484,817, and 4,597,505.
In automated plastic extrusion systems, a sensor is needed to shut down the system in the event of rupture disk failure. Such sensors that are presently used are not only large in size and weight but are very expensive. Yet it is very important to detect when pressure has raptured a disk and plastic is flowing out of the system as waste.
It would be desirable to have a reliable, low cost, disposable sensor for such plastic extruders.